Hypodermic syringe



, (No Model.)

S. W. ROBINSON & H. J. DETMERS HYPODERMIG SYRINGE.

No. 600,808; PatentedMaL. 15, 1898 tinirno stares PATENT Prion.

STILLMAN WV. ROBINSON AND HENRY J. DETMERS, OF COLUMBUS, OHIO.

HYPODERMIC SYRINGE.

SPECIFICATION forming part of Letters Patent No. 600,803, dated March 15, 1898. Application filed July 11 1896. Serial No. 598,871. (No model.)

T0 on whom it may concern:

Be it known that we, STILLMAN W. ROBIN- SON and HENRY J. DETMERS, citizens of the United States, residing at Columbus, in the county of Franklin and State of Ohio, have jections which a physician or veterinarian.

may find necessary to make.

The object of our invention is to provide a syringe which is simple in its construction, consists only of a few parts readily cleaned, is always in working order, is accurate and reliable in its action, and is easily, perfectly, and reliably sterilized by either moist heat or dry heat without any injury whatever to the syringe or any liability of affecting its working order.

In all the various uses made at the present day by physicians and veterinarians of hypo-' dermic and intravenous injections in the treatment of diseases (serum treatment, for.

instance) for the purpose of producing immunity from certain infectious diseases, such as anthrax, symptomatic anthrax, swine plague, (inc. for diagnostic purposes,as means of administering medicines which for some reason or other may be better and more effectuallyadministered in this way than by way of mouth, with the object of assuaging pain, &c., it is of the utmost importance to use a syringe that is not only at all times and under all conditions accurate and reliable in its working, but can also, with such simple means as are nearly always at hand, be perfectly and reliably sterilized without danger of injury to any of the parts thereof.

Ilypodermic syringes as heretofore constructed are objectionable in so far as their construction embodies screw-threads, seams,

and crevices, and also in the nature of the material of which they are wholly or in part com posed-as,for instance, packing with rubber, leather, cork, or other soft material, or making any of the parts of rubber or other organic matterwhich makes it practically impossible to thoroughly and completely sterilize them. A hypodermic syringe that is not or cannot be perfectly, simply, andreliably sterilized after it has been used with infectiousmaterial or on a person or animal suf fering from an infectious disease is liable to become the means of infecting the person or animal, as the case may be, on which it is used the next time. This danger is done away with and the difficulty of sterilization is overcome in the' construction hereinafter described, and set forth in the drawings, in which Figure 1 is longitudinal sectional view of a syringe embodying our invention. Fig. 2 is a longitudinal sectional View of the needlehead on an enlarged scale. Fig. 3 is alongitudinal sectional view of the cylindrical barrel, showing the needle-head removed.

Like parts are represented by similar letters of reference in' the several views.

In the said drawings, or represents a cylinder of metal and preferably formed at one end with a collar or projection a and having a bore a of uniform diameter throughout-its length, except at the end aiwhere itis formed slightly conical or outwardly flaring to receive the needle-head b, which is correspondingly tapered, as shown at o, and ground to fit in the seat a in the end of the cylinder.

Our entire aim in this invention has been to produce an instrument for the exceedingly delicate and important work required which should be entirely free from all danger of conveying contagion and endangering life therefrom. Accordingly we. have made the barrel entirely open from end to end and with an absolutely smooth surface, so that no crevices, recesses, or pockets are present to hold microbes, 850.; the entire instrument is complete in three single-piece parts, and each of these parts is entirely without foreign material, but, on the contrary, the three parts are made of metal, so that under all conditions of temperature and use the instrument is ready for perfect and instantaneous service; also, these parts contain no rubber, either hard or soft, no packing, wood, fiber, or other organic material, but are absolutely microbeproof, and may be dropped into boiling water Without injury, and will be in just as perfect working condition years hence as when new, inasmuch as there is nothing to shrink, boil out, or become permeated with foreign matter; there are no threads on any of the parts and no empty spaces in the needle-head to draw in bubbles; and other advantages of construction and use will be more fully explained below.

Too great stress cannot be laid upon the prime importance of that feature of our invention which provides a perfectly liquidtight joint between the barrel and the plunger simply by the contacting surfaces thereof, transversely lined, as presently explained, this joint not depending upon any extraneous matter and not being subject to deterioration, but being always absolutely the same and always perfect, being made simply, as stated, by the surfaces contacting throughout the entire operative areas of the barrel and plunger, said operative areas extending from the rear extremity of the barrel to the forward extremity of the plunger; and, the previouslymentioned features of construction being also borne in mind, it will be evident to the profession that this instrument affords what no other instrument has ever afforded-viz. absolute certainty of uniform action under all circumstances, so that the surgeon may place implicit reliance upon the liquid-tight operation thereof and entire freedom from drawing bubbles, &c., which, taken together with the microbe-proof construction and capability of perfect and instantaneous sterilization, enable our instrument to meet all the requirements which have been so persistently and arduously sought by the profession, but herefore without success.

Referring, further, to the drawings, it will be observed that fitted to the metallic bore a is a plunger 0, which is of uniform diameter throughout its length and is ground or otherwise fitted throughout its length to the bore of the cylinder with perfect accuracy, thereby requiring no packing or other material to prevent the passage of air between the sides of the cylinder and the sides of the barrel. This plunger is also made of metal and provided at the outer end with an enlarged knob or handle 0. We also provide on the plunger a series of small hair-like peripheral grooves, as shown at 0 extending around the periphcry of said plunger. These grooves serve the double purpose of graduations to determine the quantity of liquid drawn into or expelled from the barrel and at the same time, by reason of the elasticity of the minute filament of air contained therein, or, more properly, held thereby as an inappreciable film between the barrel and plunger, form an absolute barrier to the passage of any fluid along between the barrel and plunger, thus assisting in the perfect action of the plunger and enabling it to produce the Vacuum necessary to draw into the barrel the liquid to be used and also serving to prevent leakage of the same around the plunger as it is expelled and effectually needle 5 is extended entirely through the said head. This needle 5 is secured in the head I) by shrinking the latter thereon, by brazing, soldering, swaging, or in any other suitable manner which will make the two parts substantially integral and prevent any empty spaces to contain air and any possible joints or crevices into which micro-organisms could find their way to prevent perfect and complete sterilization. The needle and the needle-head are also slightly countersunk at the end which fits into the cylinder, as shown at 12 to give access for a fine-wire stopper for closing the needle when not in use.

The collar a on the barrel a and the handle 0 on the plunger 0 are also formed integral, or practically so, with the main body to which they belong. The result is that the operating parts of the syringe are microbe-proof and reduced to the least possible number, and the constructions are such that they can be read ily separated and thoroughly sterilized by moist heat, dry heat, or otherwise without any danger to the operating parts and without the necessity of renewing any packing or other parts which are liable to be injured or may afford hiding-places for micro-organisms, germs, or bacteria.

In forming the rings or grooves on the plunger c we preferably form them at certain intervals slightly Wider or larger than the remaining rings to facilitate the counting of the same. For instance, every fifth ring may be slightly larger, as is usually the case in making graduations. The rings are also made at such distances apart as to measure a certain definite space within the barrel of the cylinder, such as a fractional part of a cubic centimeter or of any other unit of capacity.

Having thus described our inventiom we claim The combination of a metallic barrel having a uniform bore throughout the operating portions of its length but formed slightly conical at the needle end to receive a needle-head which is correspondingly tapered and fitted to said barrel, a perforated needle extending through said head and joined thereto so that the parts are substantially integral, and a me tallic plunger of uniform diameter through- In testimony whereof-we have hereunto set out its length fitted to said barrel, Without our hands this 29th day of J une, A D. 1896. the aid of packing material, said plunger be- STILLMAN W. ROBINSON. ing provided with fine peripheral grooves HENRY J. DETMERS.

5 adapted to form the double purpose of pack-' Witnesses:

ing and a graduated scale, substantially as FRANK RATHMELL, and for the purpose specified. ROBERT H. HASSLER. 

